OBD1 ECU pinout – Honda, GM, Ford [Updated list]

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OBD1 ECU pinout - Honda, GM, Ford

Honda OBD1 ECU pinout

This part shows you the OBD1 ECU pinout (locations and wire colors) for all M/T ’92-95 Civic / ’92-95 Integra / ’92-95 Prelude VTEC and NON-VTEC vehicles.

Honda OBD1 ECU pinout diagram

Connector A

honda obd1 pinout connector A
Pin numberPin nameDescription Wire color
1INJ1Injector 1Brown
2INJ4Injector 4Yellow
3INJ2Injector 2Red
4VTSVTEC solenoidOrange/White
5INJ3Injector 3Light blue
6PO2SHTCPrimary O2 sensor heater control
Civic VX D15Z1: HTCNTL (5-wire O2)
7FLRFuel pump relay Civic: Green/Yellow
Integra: Green/Blue
8Empty slot----
9IACV Idle air control valveGreen/White
10Empty slot----
11EGRExhaust gas recirculation solenoid valve
Civic SOHC or ysed for H22/H23 EGR
Red or Orange/Blue
12FANCRadiator fan controlYellow/Green
13MILMalfunction indicator lightGreen/Orange
14Empty slot----
15ACCA/C compressor clutch Black/Red
16ALTCAlternator controlWhite/Green
17IABIntake air bypass
(Integra GSR B18C)
18TCMTransmission control module
Empty slot for 5SPD Civic and Integra
19ICSIntake control solenoid (H22A)
Empty slot for Civic and Integra
20PCSEvap purge control solenoid valveRed
21ICMIgnition control moduleRed/Green
22ICMIgnition control module
Note: Depin this when using an OBD1 AEM EMS
23PG1Power groundBlack
24PG2Power groundBlack
25IGP2Power sourceYellow/Black
26LG1Logic groundBlack/Red

Connector B

honda obd1 pinout connector B
Pin numberPin nameDescription Wire color
1IGP1Power groundYellow/Black
2LG2Logic ground Brown/Black
3TCMTransmission control module
Empty slot for 5SPD Civic and Integra
4TCMTransmission control module
Empty slot for 5SPD Civic and Integra
5ACSA/C Switch signal Blue/Red
6Empty slot----
7M/TClutch switch (Civic VX only)
Also used for A/T function
Pink/Black or Green (A/T)
8PSPSWP/S power switch signal
Empty slot for Civic CX/DX/LX/EX/Si
Empty slot for Integra
Starter signal switch
Transmission related
- Civic: Blue/White
- Integra: Blue/Red
- Civic: Grey
- Integra: Yellow
10VSSVehicle speed sensorYellow or Blue/Orange
11CYP PCylinder position sensor side P (detection) Orange
12CYP MCylinder position sensor side M (ground)White
13TDC PTop dead center sensor side PP(detection) Orange/Blue
14TDC M Top dead center sensor side M (ground)White/Blue
15CKP PCrankshaft position sensor side P (detection) Blue/Yellow
16CKP M Crankshaft position sensor side M (ground)Blue/Yellow

Connector D

honda obd1 pinout connector D
Pin numberPin nameDescription Color
1VBUVoltage back upWhite/Blue or White/Yellow
2BKSWBrake switchGreen/White
3KSKnock sensor
Empty slot for Civic CX/DX/EX/Si
Civic VX D15Z1: LAF sensor (5-wire O2)
4SCSService check signalCivic: Brown
Integra: Brown/White
5Empty slot----
6VTPS/VTMVTEC pressure switchOrange/Blue or Light blue
7TXD/RXDDiagnostic data link Light blue or Light green/Red
8LAF sensor (5-wire O2) VS+
Only Civic VX D15Z1, others are empty--
9ALT FRAlternator FR charge signal Pink or White/Red
10EL (ELD)Electrical load detectorGreen/Red or Green/Black
11TPSThrottle position sensor Light green or Red/black
12EGRLEGR valve lift sensor (only Civic VX)White/Black
13ECTEngine coolant temp sensorRed/white or Yellow/Blue
14PHO2Primary heated O2
Civic CX D15B8: 1-wire O2
Civic VX D15Z1: LAF sensor (5-wire O2) IP+
White or White/Red
15IATIntake air tempRed/Yellow
16LAF sensor (5-wire O2) IP-, VS-Only Civic VX D15Z1
Empty slot for the others
17MAPManifold absolute pressure sensorCivic: White
Integra: White/Blue
18Inter lock control unit (A/T related)
Civic CX/VX optional up-shift LT
Empty slot for the others
19VCC1Sensor voltage for MAPCivic: Yellow/Green
Integra: Red/white
20VCC2Sensor voltage for TPSYellow/White
21SG1Sensor ground 1Civic: Green/Blue
Integra: Blue/White
22SG2Sensor ground 2Green/White

GM OBD1 pinout

GM OBD1 pinout diagram

Ford OBD1 pinout

Ford OBD1 pinout diagram
Pin numberDescription
1Fuel pump enable output
2Not used
3Malfunction indictor lamp (MIL) output
4K diagnostic line
Data +
5Data -
6L diagnostic line
Sensor signal return

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